Flight 772 carrying 181 passengers and six crew turned around approximately 45 minutes into the flight as it passed over West Virginia, a spokeswoman for the Sunwing airline told AFP.
Captain Jennifer Stadnyk at North American Aerospace Defense Command said two F16 fighter jets were diverted to escort the jetliner back to Toronto, where it landed safely and the passenger was arrested by police.
Video taken by other passengers and circulated online showed officers in body armor and helmets boarding the plane with weapons drawn.
Witnesses told local media the suspect had become agitated during a conversation with flight attendants and declared that he had a bomb and would destroy the plane.
Ali Shahi was charged with mischief, uttering threats and endangering an aircraft's safety.
Sunwing said the other passengers were "generally in good spirits" and were scheduled to depart for Panama later in the afternoon.